The local DNA conformation in the region of transcription factor binding sites, determined by context, is one of the factors underlying the specificity of DNA-protein interactions. Analysis of the local conformation of a set of functional DNA sequences may allow for determination of the conservative conformational and physicochemical parameters reflecting molecular mechanisms of interaction. The web resource SITECON is designed to detect conservative conformational and physicochemical properties in transcription factor binding sites, contains a knowledge base of conservative properties for >100 high-quality sample sites and allows for recognition of potential transcription factor binding sites based on conservative properties from both the knowledge base and the results of analysis of a sample proposed by a user. The resource SITECON is available at http://wwwmgs.bionet.nsc.ru/mgs/programs/sitecon/.